This invention relates to electronics in general and more particularly to liquid crystal displays.
The use of liquid crystal displays has achieved widespread acceptance in a variety of applications. Large numbers of commercially available liquid crystal displays can be purchased with standard sevensegment displays having two, four or more numerals therein, as well as other liquid displays for showing standard analog representations, for example bar graphs. The use of multiple displays on a single crystal however usually will require a customized display and therefore the cost for custom layout and tooling work is prohibitive for short run production items having relatively severe cost restrictions.
In many typical applications, tne liquid crystal display is electrically interconnected to a parallel mounted printed circuit board utilizing elastomeric connectors of the proper dimensions, wherein each connector has a number of striated conduction zones such that the liquid crystal display having electrical contacts deposited on the back surface of the crystal is pressed firmly against the elastomeric connector which in turn is held against the printed circuit board. The printed circuit board additionally has coincident electrical contacts thereon and if the pressure holding the liquid crystal display is sufficient, good electrical contact is made to each of the contacts without interference from the others and furthermore the elastomeric connector provides a limited degree of shock protection for the crystal and is therefore a preferred method of assemblying and mounting liquid crystal displays.
Typically a structure housing two or more liquid crystals will utilize a bezel formed facing providing sufficient strength to compress the viewing surfaces of the crystals over the electrical contact regions. The strength required of these bezel structures also mandates a substantial thickness in the bezel itself. This necessary thickness results in a restricted viewing angle since the bezels protrude from the viewing surface of the display. A cover glass utilized to clamp the crystals in place will necessarily have its clamping force applied to the entire surface of the displays, and therefore must be relatively thick to provide sufficient force to provide a good electrical contact.
One problem which has been noted when multiple crystals are mounted in the same display is the tendency for the cover glass to deform outwardly away from the crystals in those regions of the display which are a relatively large distance from the edge and therefore not in proximity to the window clamping or supporting apparatus. This problem results in a tendency to make poor electrical contacts to those portions of liquid crystals near the center of a multiple crystal display.